Fuel temperature control for internal-combustion engines



M. MALLORY FUEL TEMPERATURE CONTROL FOR June 21,1949.

INTERNAL-COMBUSTION ENGINES Filed Jan. 10, 1946 FIG-I MARION MN-LORY INVENTOR ATTORNEYS.

Patented June 21, 1949 UNITED STATES PATENT orrlca FUEL TEMPERATURE CONTROL FOR INTERNAL-COMBUSTION ENGINES Marion Mallory, Detroit, Mich.

Application January 10, 1946, Serial No. 640,222 4 Claims. (Cl. 123 -122) This invention relates to a fuel temperaturecontrol for an internal combustion engine.

It is common practice in internal combustion engines to provide a hot spot under the carburetor over which the fuel passes. This hot spot assists in the atomizationof the fuel. The hot spot is heated by the exhaust gases of the engine. In such a, system a valve is located in the exhaust manifold for controlling the flow of exhaust gases so that a greater volume of exhaust gases pass around the hot spot when the engine is cold than when the engine is hot. In some cases the heating of the hot spot is regulated by the velocity of the exhaust gases and in other cases by thermostatic means which control the opening and closing of the valve. In such system the valve shafts often overheat due to the excessive heat in the exhaust gases and the valves stick. If the valve shafts are mounted loose enough to avoid stick-'- ing, then exhaust gases escape under the engine hood which find their way into the vehicle. If v the control valve is operated by exhaust velocities and the engine is operated under part throttle. the valve will be almost closed due to the low exhaust velocities and the hot spot will get hot, but if the throttle is suddenly opened for full charge, the hot spot will not cool off quickly enough.

This causes the charge to be expanded and in' turn cause detonation and lost power. After the hot spot cools ofi when operating under wide open throttle and the carburetor throttle is brought to apart throttle condition, then the hot spot is cold and will take too long to warm up.

It is the object of this invention to overcome the delay inheating the fuel charges when the throttle is'moved from a wide open position toward a closed position and to overcome the delay in cooling the fuel charges when the throttle is moved from part open position to wide open position, and at the same time to increase the r velocities of the charge going to the engine cylin- 1 engine remains hot.

his

the butterfly type controlling the main fuel intake passageway 4 and the auxiliary fuel intake passageway 5. Valves 2 and 3 are mounted on a common shaft and positioned in perpendicular planes so that valve 2 opens as valve 3 closes and vice versa. Valves 2 and'3 are located between carburetor throttle I and the engine. Thermostat 8, which is a helical coil bimetal type thermostat, connected by-link l to crank arm I9 fixed on valveshaft 20 which carries valves 2 and 3. Link 1 is connected to arm I8 of thermostat 6 with a lost motion connection in the form of an elongated slot 2| in which the bent end 22 of link I slides. Suction device 8 is connected to orifice I I in the intake passageway 23 on the engine side of valve I by conduit IIl. Diaphragm 24 of suction device 8 is connected by link- 9 with crank 25 mounted on the end of shaft 20 opposite crank I9. Spring 26 acts against diaphragm 24 and through link 9 tends to hold valve 2 open.

4 The operation of my system is as follows: As-

suming that the engine is cold, thermostat 6, acting through the lower end of slot 2 I, link I, crank I9 and shaft 20, will tend to hold auxiliary valve 3 open and valve 2 closed and the fuel will now pass through manifold 5 which is in heat exchange relation with the exhaust gases flowing through chamber 21. Arm I8 of thermostat 6 moves clockwise as the temperature rises and counterclockwise as the temperature falls. Thermostat 6 will be positioned in heat exchange relation with the engine and for this purpose can be mounted on the carburetor or on the engine block or on the exhaust manifold. Spring 26 tends at all times to open valve 2 and close valve 3. After the engines get hot thermostat 6 will have moved arm I8 down or clockwise sufficiently so that end 22 of link 1 will be free or above the lower end of slot 2i and thermostat 6 will have no further effect on valves 2 and 3 as long as the However, suction device 8 will now operate throttles 2 and 3 in accordance with the pressure conditions in the intake passageway 23 on the engine side of valve I; for example, if throttle I is wide open, the pressure will be high at orifice II, which pressure will be come established in the suction chamber of suction device 8 so that suction device 8 will hold valve 2 open and close va ve 3. When throttle I is moved toward closed position, the pressure at orifice II will drop, that is, the vacuum at orifice II in passageway 23 will rise thereby causing 'suction device 8 to move throttle 2 toward closed position and throttle 3 toward an open position. Thus, in my device the heat exchange between the exhaust gases 21 and auxiliary asraeos manifold s is continuous so that manifold I is never cooled down. Thus. when the engine is cold, as shown in Fig. 1, or operating under light load or part throttle, Fig. 1, the fuel charge is passed through thehot spot or heated passageway I preparatory to entering the engine combustion chamber and when the engine is operating at wide open throttle or is hot, then valve 8 is olosednnd the fuel passes through the main intake passageway l preparatory to entering the exhaust gases because this is the most economical way of heating the charge. However, any other combustion chamber and hot'spot passageway l is bypassed.

By this operation I obtain immediate response or change in fuel temperatures in changing the load of the engine by throttle operation and I also increase the velocity and the temperature of the fuel charge when the engine is cold or working under light load. When the engine is cold and throttle valve I is open wide, then thermostat 8 will oppose suction device 8 so that valve 2 will remain closed and valve 8 open. In other words, bimetal coil 8 is more powerful than spring 28 in suction device 8 so that spring 28 cannot open valve 2 as long as the engine temperature is such that coil 8 opposes opening of valve 2. When the engine is cold, end 22 of link I will be positioned at the bottom of slot 2I so that any torque applied on shaft 20 by spring 28 will be ineflective to rotate valve shaft 28 and arm I8 downwardly which would be necessary to the opening of valve 2 and the closing ofvalve 8. However. as soon as the engine gets hot, arm I8 moves clockwise to bring end' 22 of link 1 adjacent the upper endof slot 2Iyso that under such condition spring 28 of suction device lcan open valve 2 whenever throttle valve j passageway pres- I is opened to raise the intake sure at orifice II.

In Fig. 2 the elements are numbered as follows: auxiliary valve I2 of the butterfly type connected by link I8 with suction device 8 and manner of heating the charge in or I! could be used.

above it will be seen that my device auxiliary pastransfers the fuel charge into a cold intake mani- -,foldforwideopenthrottl eoperation when the engine is hot and transfers the fuel charge into Y a hot manifold "for part throttle operation and for part and 'full'throttle operation when the engine is cold. Since the passageways 8 and I1 are always hot, the temperature change of the fuel for different throttle positions is immediately changed and there is no sticking of the controls. With m'ydevice the charge can be heated to a much higher degree or temperature than in other systems because it is immediately changed from a hot manifold to a cold manifold at wide open throttle which givesthe highest volumetric efciency for wide open throttle a d'makes possible a colder charge at higher com ression' for wide by link It with arm I 8 of thermostat 8, carburetor throttle valve II of the butterfly type, auxiliary passageways I'I leading to the intake ports of the engine. Passageways II are surrounded by chamber 8t through which the hot exhaust gases from the engine flow.

In the form shown in Fig. 2, when the engine is cold thermostat 8 will tend to hold valve I2 closed and the fuel charge will be passed through the heated intake passageways I I preparatory to entering the combustion chamber. Here again under such conditions, even though throttle I! be opened wide, the coil spring 28 in suction device 8 cannot open valve I2 because bimetal coil 8 is more powerful and will oppose such opening. As soon as the engine gets hot, thermostat 6 will move arm I8 clockwise causing the end 22 of link It to move relatively downwardly in slot 2I and the thermostat will have noeflect on valve I2. Valve I2, as long as the engine is hot, will be opened and closed in response to pressure conditions in the intake passageway 23 at orifice II on the engine device 8 will open valve I 2 as the pressure rises at orifice II due to-the opening of throttle I8 and suction device 8 will move valve I2 toward closed position as throttle valve I8 is moved toside of valve I5 and suction open throttle and a hotter charge for part throttle operation which, in eifect. gives higher compression at part throttle.

Preferably passageway s is smaller in cross section than passageway 4. Therefore, when valve lis open and valve 2 closed, the velocity of the fuel charge will be greater than when the charge is passing through passageway 4.

Hence, at part throttle and when the engine is cold, the velocity of the fuel charge passing through the intake passageway I in my engine will be higher than when the engine is hot and the throttle is wide open, in which case the fuel charge will be flowing through the main intake passageway l. The direction of flow of the charge is indicated y. the arrowsin Figs, 1 and 2.

I claim: 1. In an internal combustion engine having an intake passageway for supplying motive fluid to said engine, a throttle valve controlling the flow of motive fluid therethrough, heating means, a second passageway for supplying motive fluid to the engine inheat exchange relation with said heating means and communicating with the first intake passageway on the engine side of said throttle valve, valve means independent of said throttle valve for controlling the flow of motive fluid through said intake passageways on the engine side of the throttle valve, said valve means being constructed and arranged to decrease the flow of motive fluid through the first mentioned intake passageway as it increases the flow through the heated passageway, a thermostat in heat exchange relation with said engine and having a lost motion connection with said valve means whereby said thermostat when the engine is cold controls said valve means to increase the flow of motive fluid through said second passageway and when the engine is hot the thermostat owing to its lost motion connection is ineffective to actuate said valve, and a fluid pressure motor actuated in response to changes of pressure in the intake passageway on the engine side of said throttle valve and between said throttle valve and said valve means whereby-said pressure actuated means when the engine is hot responds to a rise in intake passageway pressure to increase the flow of motive fluid through the first intake passageway and decrease the flow through the heated passageway and responds to a fall in intake passageway pressure to increase the flow or motive fluid through the heated passageway and decrease the flow through'the other passageway.

2. In an internal combustion engine having a main intake passageway for supplying motive fluid to said engine, a throttle valve in said passageway controlling the flow of motive fluid therethrough, heating means, a bypass passageway communicating with the intake passageway on the engine side of said throttle valve for conducting motive fluid to said engine, said bypass passageway being in heat exchange relation with said heating means, two separate valves one mounted in the heated passageway and the other in the main intake passageway and constructed and arranged so that as the one valve closes the otheropens, temperature responsive means in heat exchange relation with said engine, a lost motion connection between said temperature responsive means and said two last mentioned valves, said temperature responsive means respending to a fall in engine temperature to increase the flow of motive fluid through said bypass passageway and decrease the flow through the main intake passageway, and means actuated by changes in intake passageway pressure on the engine side of said throttle valve and a connection between said pressure actuated means and said last two mentioned valves for controlling said valves and the flow oi motive fluid through said passageways in response to changes in intake passageway pressure when the engine is operating above a predetermined temperature, said temperature responsive means due to said lost motion connection being ineffective to control said valves and the how of motive fluid through said passageways when the engine is operating above said predetermined temperature whereby said pressure actuated means in response to aiall in the intake passageway pressure moves the valve in the main intake passageway toward closed position and the valve in the heated passageway toward open position. I i 3. In an internal combustion engine having an intake passageway for supplying motive fluid to said engine, a throttle valve in said passageway controlling the flow of motive fluid therethrough, heating means, a bypass passageway communicating with the intake passageway on the engine side of said throttle valve for conducting motive fluid to said engine, said bypass passageway being in heat exchange relation with said heatin means, valve means in said bypass passageway and intake passageway on the engine side of said throttle valve for controlling the flow of motive fluid through said passageways separate from the throttle valve, temperature responsive means in heat exchange relation with said engine, a lost motion connection between said temperature responsive means and said "valve means whereby said temperature responsive means is ineflectiye a perature whereby as said intake passageway pressure rises the valve means tends to decrease the flow oi motive fluid through said bypass passageway and increase the flow of motive fluid through the intake passageway, said temperature responsive means due to said lost motion connection being inefiective to control the flow of motive fluid through said passageways when the engine is operating above said predetermined temperature and said temperature responsive means being more powerful than said pressure actuated means whereby said pressure actuated means is ineffective to control the flow of motive fluid through said passageways when the engine is operating below another lower predetermined temperature, said temperature responsive means and said pressure actuated means both influencing said valve means in the temperature range between said predetermined temperatures.

a. In an internal combustion engine having an intake passageway for supplying motive fluid to said engine, a throttle valve in said passageway controlling the flow of motive fluid therethrough, heating means, a bypass passageway communieating with the intake passageway on the engine side of said throttle valve for conductingmotive fluid to said engine, said bypass passageway being in heat exchange relation with said heating means, a valve for controlling the flow oi motive fluid through said bypass passageway, a second valve for controlling the flow of fluid through the intake passageway, said last two mentioned valves being positioned on the engine side of said throttle valve and constructed and arranged so that as the one valve opens the other valve closes their respective passageways, thermostatic means in heat exchange relation with said engine, a lost mo= tion connection between said thermostatic means and said last two mentioned valves whereby the thermostat when the engine is cold closes the valve in the intake passageway and opens the V valve in the bypass passageway and when the control said valve.

to actuate said valve means when the engine is operating above a predetermined temperature and whereby upon a fall in engine temperature, the temperature responsive means actuates the valve means to increase the flow oi motive fluid through said bypass passageway and decreases the flow through said main intake passageway, and means actuated by changes in intake passageway pressure on the engine side of said throttle valve having a connection with said valve means for controlling said valve means in response to changes in intake passageway pressure when the engine is operating above a predetermined tem- 75 engine is hot the thermostat owing to its lost motion connection is ineffective to actuate said valves, a fluid pressure motor connected to said last two mentioned valves, a conduit connecting said fluid pressure motor with the intake passageway on the engine side of the throttle valve whereby when the engine is operating above a predetermined temperature said fluid pressure motorresponds to a rise in intake passageway pressure to open said intake valve and close said bypass passageway valve, the said thermostat when the engine is cold being constructed and arranged so that it exerts greater power on said valves than the said fluid pressure motor whereby the said fluid pressure motor is ineffective; to

MARION MALLORY. REFERENCES crrEn The following references are of record in the file of thispatent:

UNITED STATES PATENTS Number Name Date 1,415,086 Church May 9, 1922 1,448,008 Smith Mar. 13, 1923. 2,004,093 Dean 81; al. June 11, 1935 2,082,397 HiSCOOk "June 1, 1937 FOREIGN PATENTS Number Country I Date Great Britain Oct. 9. 1924 

